From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932260Ab3GVLEI (ORCPT ); Mon, 22 Jul 2013 07:04:08 -0400 Received: from cassiel.sirena.org.uk ([80.68.93.111]:48325 "EHLO cassiel.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932170Ab3GVLEG (ORCPT ); Mon, 22 Jul 2013 07:04:06 -0400 Date: Mon, 22 Jul 2013 12:03:41 +0100 From: Mark Brown To: Andrea Adami Cc: linux-mmc@vger.kernel.org, Chris Ball , Russell King , linux-kernel@vger.kernel.org, Marko Katic Message-ID: <20130722110341.GR9858@sirena.org.uk> References: <1374361668-3184-1-git-send-email-andrea.adami@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="PEWkPmBCIbC5Tcj0" Content-Disposition: inline In-Reply-To: <1374361668-3184-1-git-send-email-andrea.adami@gmail.com> X-Cookie: You will be awarded some great honor. User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 94.175.92.69 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH] mmc: pxamci: Refactor regulator support X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:57:07 +0000) X-SA-Exim-Scanned: Yes (on cassiel.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --PEWkPmBCIbC5Tcj0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Sun, Jul 21, 2013 at 01:07:48AM +0200, Andrea Adami wrote: > The ADS7846 driver _requires_ the use of a voltage regulator > or if not present, CONFIG_REGULATOR_DUMMY should be used for proper operation. > This was made mandatory by the following commit: No, CONFIG_REGULATOR_DUMMY should *never* be used in production. > The ADS7846 in spitz machines is not connected to > any power regulator so it needs CONFIG_REGULATOR_DUMMY enabled. I don't think that's the case, it would be a very unusual piece of silicon that was able to operate without power. It may be that it's not using a software controllable regulator but there will be one or more power supplies. Judging by your problem here it seems like there is actually a software controllable regulator though... > However, enabling CONFIG_REGULATOR and CONFIG_REGULATOR_DUMMY > will break pxamci driver and cause the following error output: This is why you should never use CONFIG_REGULATOR_DUMMY in production, it's just a crutch to help things boot during development. > Regulator support in pxamci_init_ocr() is not > written with the existence of the dummy regulator driver in > mind. It does not check the return value of mmc_regulator_get_ocrmask() > and it will only fall back to platform data if no regulator was found. No regulator driver should be written with CONFIG_REGULATOR_DUMMY in mind. My guess here is that your custom callbacks for this board should be being replaced by a regulator, for example the fixed voltage regulator if there's only one voltage supported. --PEWkPmBCIbC5Tcj0 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.20 (GNU/Linux) iQIcBAEBAgAGBQJR7RGKAAoJELSic+t+oim9YkQP/11tnhVpDCcb9F0M8CafRWrb uGb4LLPtNaCTac0r2JPt6RA6aeROEdX1eiwZxG6UiEn/HGkXsnSLw2DhYzd260mW Aau8jwMhCuI1VfGYomc0c9IMBQoM+yo1nIAyKTYqvLr/eFHWrglgpNYEY7LIlyxd NT94As+hf3zyM9Nul8HQ3iDkdJriGkaLf2/62IJ++CKNpvh4FwtqEBfXo1ycOgf0 mhPi5jWqx0fASYHkYptXHrKmSlKbDsbpzcDPgQBPE6IPMsiMTSW1zbDHlXPUyjI5 StJ/bd22ET7kPe13xMXbscMNtXfujdryaTmQFO4fQnfNRbMni1Il3wHJO+1eOsfJ eXquimxrUXxU50h/YBWhlM61orVcMx5AXIoYW7dJATEEsQA+8IPpSiod3rFGRXxh 21Cy1y1/Eja4RACSkNit5lUJVw8hjGTox+cz5GgPg5fnah0BSl8/AzZlilf0d5Pf /KuMnWwrELh1rXgCzaJZ8Ax5Gbo86bQ4H5uoM3SUAzyhA3mPMEgwLW/DIvK2aH8t NroB3iV1mXk1eA30ePhlPoZocnY36VUSqrmTJZoRSD2mZNUBlCZ3bAjHWqj41xEe dIFGKdStyL21CsTd0oS7wYaTAvICNkuUIFvd8jYcGsxmpXCJJJoQqnE2jqO+O4hj wwFcnSzh/Ts81hsj26Z/ =F/nN -----END PGP SIGNATURE----- --PEWkPmBCIbC5Tcj0--